Method and system for post-etch treatment of patterned substrate features

Abstract

A method of patterning a substrate, comprises providing a set of patterned features on the substrate, exposing the set of patterned features to a dose of ions incident on the substrate over multiple angles, and selectively etching exposed portions of the patterned features.

What is claimed is: 
     
       1. A method of patterning small features in a substrate, comprising;
 patterning a resist layer disposed on the substrate; 
 etching the substrate while the patterned resist layer is in place to define patterned substrate features having sidewalls; 
 removing the resist layer; 
 exposing the patterned substrate features to ions at a set of incident angles to create altered portions of the sidewalls; and 
 etching the altered portions of the sidewalls. 
 
     
     
       2. The method of  claim 1 , wherein the dose of ions is arranged to produce a damage interface within sidewalls of the patterned features that defines a smoother surface than an initial surface of the sidewalls. 
     
     
       3. The method of  claim 1 , wherein the patterned substrate features are one of a polycrystalline semiconductor, a single crystalline semiconductor, and an insulator material. 
     
     
       4. The method of  claim 1 , wherein the ions are arranged to implant into the substrate to a first depth so as to define an etch-resistant inner region having a predetermined thickness. 
     
     
       5. The method of  claim 1 , wherein the set of angles comprises a multiplicity of angles. 
     
     
       6. The method of  claim 5 , wherein the exposure comprises arranging the substrate at a multiplicity of orientations with respect to an ion beam of a beam-line implantation system. 
     
     
       7. The method of  claim 1 , wherein the exposure comprises an exposure to ions extracted from a plasma using a plasma sheath modifier that provides ions to the substrate over an angular range.